Removal of NO with Fe(II)NTA solution catalyzed by the carbon treated with ethylenediamine

[Fe(II)NTA]-(NTA, nitrilotriacetic acid) may lose its ability to bind NO due to the oxidation of [Fe(II)NTA]- to [Fe(III)NTA] by oxygen in the flue gases. NO removal efficiency will decrease quickly because of the decline of [Fe(II)NTA]- concentration. Activated carbon is used to catalyze the reduction of [Fe(III)NTA] to [Fe(II)NTA]- by sulfite to retain the ability of absorbing NO in the simultaneous removal of NO and SO2. Ethylenediamine solution is capable of changing the physical structure and chemical characteristics on the carbon surface to improve the catalytic capability of activated carbon. The experiments suggest that the best activated carbon be generated by immersing the original carbon in 5.0 mol L-1 ethylenediamine solution for 6 h followed by being heated at 700 degree celsius in N-2 for 4 h. The modification with ethylenediamine increases the surface area and alkalinity on the carbon. The experiments also indicate that the removal efficiency of nitric oxide is increased from 52.1-54.4 to 73.7-77.3% as the [Fe(II)NTA]- regeneration is catalyzed by the modified carbon instead of the original one.